Sensor coupling verification in tandem compressor units

Abstract

Provided are a method and apparatus for verifying or correcting the temperature sensor and compressor pairings within the HVAC system control logic, indicating that a sensor is logically paired with the specific compressor, from amongst a tandem compressor group, to which the sensor is coupled.

The invention claimed is: 
     
       1. An apparatus for verifying that one or more sensors are coupled to an associated compressor of an HVAC system, comprising:
 a first compressor having a first discharge pipe leg coupled to a discharge port of the first compressor; 
 a second compressor having a second discharge pipe leg coupled to a discharge port of the second compressor, wherein the second discharge pipe leg merges with the first discharge pipe leg to form a common discharge pipe shared by the first and second compressors; 
 a first sensor coupled to the first discharge pipe leg, the first sensor configured to transmit a first signal to a location remote to the first sensor, the first signal indicating one or more temperatures of refrigerant within the first discharge pipe leg; 
 a controller implemented with logic, wherein the logic is configured to compare data received by the controller from the first sensor, wherein the controller is operably coupled to the first and second compressors to switch each of the first and second compressors between energized and de-energized states, the controller having a control configuration comprising: causing a temperature increase of the refrigerant within the first discharge pipe leg of the first compressor;
 receiving from the first sensor the first signal indicating one or more temperatures of refrigerant within the first discharge pipe legs; 
 determining whether the first signal indicates one or more temperatures above a threshold value; 
 if the first signal indicates one or more temperatures above the threshold value, generating a first pairing signal indicating the first sensor is coupled with the first compressor; and 
 if the first signal indicates one or more temperatures below the threshold value, generating a second pairing signal, wherein the controller is configured to determine that the first sensor is not coupled with the first compressor in response to generating the second pairing signal. 
 
 
     
     
       2. The apparatus of  claim 1 , wherein the control configuration further comprises:
 energizing the first compressor while de-energizing and maintaining the second compressor in a de-energized state causing a temperature increase of the refrigerant within the first compressor, whereby compressed and heated gaseous refrigerant flows through the first discharge leg. 
 
     
     
       3. The apparatus of  claim 1 , further comprising:
 a second sensor coupled to the second discharge pipe leg, the second sensor configured to transmit a second signal to a location remote to the second sensor, the second signal indicating one or more temperatures of refrigerant within the second discharge pipe leg. 
 
     
     
       4. The apparatus of  claim 3 , wherein the threshold value to which the first signal is compared comprises one or more temperatures of refrigerant within the second discharge pipe leg indicated by the second signal. 
     
     
       5. The apparatus of  claim 3 , wherein the first and second sensors are thermistors. 
     
     
       6. The apparatus of  claim 4 , further comprising:
 a first crank case heater coupled to the first compressor and configured to heat the refrigerant within the first compressor when the first crank case heater is energized, wherein one or more temperatures of refrigerant within the first compressor are indicated by the first signal transmitted by the first sensor when the first sensor is coupled to the discharge port of the first compressor; 
 a second crank case heater coupled to the second compressor and configured to heat the refrigerant within the second compressor when the second crank case heater is energized, wherein one or more temperatures of refrigerant within the second compressor are indicated by the second signal transmitted by the second sensor when the second sensor is coupled to the discharge port of the second compressor; 
 the controller operably coupled to switch each of the first and second crank case heaters between energized and de-energized states, wherein the control configuration further comprises:
 energizing the first crank case heater while de-energizing and maintaining the second crank case heater in a de-energized state causing a temperature increase of the refrigerant within the first compressor; 
 receiving from the first and second sensors the first and second signals indicating one or more temperatures of refrigerant within the first and second discharge pipe legs; 
 identifying which of the first and second signals indicates a higher temperature; 
 if the first signal indicates one or more temperatures higher than the one or more temperatures indicated by the second signal, generating a third pairing signal indicating the first crank case heater is coupled with the first compressor; and 
 if the first signal indicates one or more temperatures not higher than the one or more temperatures indicated by the second signal, generating a pairing fourth signal indicating the first crank case heater is not coupled with the first compressor. 
 
 
     
     
       7. The apparatus of  claim 1 , wherein the control configuration further comprises:
 the controller receiving a triggering input signal and, in response to the triggering input signal, causing a temperature increase of the refrigerant within the first discharge pipe leg of the first compressor. 
 
     
     
       8. The apparatus of  claim 7 , wherein the triggering input signal indicates a partial load demand on the HVAC system. 
     
     
       9. The apparatus of  claim 7 , wherein the triggering input signal indicates an initial powering of the HVAC system. 
     
     
       10. The apparatus of  claim 7 , wherein the triggering input signal indicates a command for diagnostic testing of the HVAC system. 
     
     
       11. The apparatus of  claim 4 , wherein the control configuration further comprises:
 after expiration of a period of time following energizing the first compressor while de-energizing and maintaining the second compressor in a de-energized state, identifying which of the received first and second signals indicates a higher temperature. 
 
     
     
       12. The apparatus of  claim 3 , wherein the control configuration further comprises:
 monitoring, if the first pairing signal is generated, operation of the first compressor using the first signal. 
 
     
     
       13. The apparatus of  claim 12 , further comprising:
 the first compressor having a first suction pipe leg coupled to a suction port of the first compressor; 
 the second compressor having a second suction pipe leg coupled to a suction port of the second compressor; 
 wherein the first and second suction pipe legs each diverge from a common suction pipe shared by the first and second compressors; and 
 a third sensor coupled to the common suction pipe, the third sensor configured to transmit a third signal to a location remote to the third sensor, the third signal indicating one or more pressures of refrigerant within the common suction pipe. 
 
     
     
       14. The apparatus of  claim 13 , wherein the control configuration further comprises:
 determining, if the first pairing signal is generated, a superheat temperature of the refrigerant within the first compressor using at least the first signal indicating one or more temperatures of refrigerant within the first discharge pipe leg and at least the third signal indicating one or more pressures of refrigerant within the common suction pipe. 
 
     
     
       15. A method of verifying the couplings of one or more sensors to an associated compressor of an HVAC system, the method comprising:
 coupling a first discharge pipe leg to a discharge port of a first compressor; 
 coupling a second discharge pipe leg to a discharge port of a second compressor; 
 coupling the first and second discharge pipe legs to a common discharge pipe shared by the first and second compressors; 
 coupling a first sensor to the first discharge pipe leg, the first sensor configured to transmit a first signal to a location remote to the first sensor, the first signal indicating one or more temperatures of refrigerant within the first discharge pipe leg; 
 operably coupling a controller to the first and second compressors, wherein the controller is implemented with logic, wherein the logic is configured to compare data received by the controller from the first sensor, wherein the controller is operably coupled to the first and second compressors for switching each of the first and second compressors between energized and de- energized states; 
 coupling the controller to the first sensor for receiving the first signal indicating one or more temperatures of refrigerant 
 within the first discharge pipe leg, causing, using the controller, temperature increase of the refrigerant within the first discharge pipe leg of the first compressor; 
 receiving, using the controller, the first signal from the first sensor indicating one or more temperatures of refrigerant within the first discharge pipe leg; 
 determining, using the controller, whether the first signal indicates one or more temperatures above a threshold value; 
 responive to a determination that the first signal indicates one or more temperatures above the threshold value, 
 generating, using the controller, a first pairing signal indicating the first sensor is coupled with the first compressor; 
 determining, using the controller, whether the first signal indicates one or more temperatures below the threshold value; and responsive to a determination that the first signal indicates one or more temperatures below the threshold value, 
 generating, using controller, a second pair signal, wherein the controller is configured to determine that the first sensor is not coupled with the first compressor in response to generating the second pairing signal. 
 
     
     
       16. The method of  claim 15 , further comprising:
 coupling a second sensor to the second discharge pipe leg, the second sensor configured to transmit a second signal to a location remote to the second sensor, the second signal indicating one or more temperatures of refrigerant within the second discharge pipe leg; 
 coupling the controller to the second sensor for receiving the second signal indicating one or more temperatures of refrigerant within the second discharge pipe leg; and 
 receiving, using the controller, the second signal from the second sensor indicating one or more temperatures of refrigerant within the second discharge pipe leg. 
 
     
     
       17. The method of  claim 16 , wherein the threshold value to which the first signal is compared comprises one or more temperatures of refrigerant within the second discharge pipe leg indicated by the second signal. 
     
     
       18. The method of  claim 17 , wherein the first and second sensors are thermistors. 
     
     
       19. The method of  claim 16 , further comprising:
 coupling a first suction pipe leg to a suction port of the first compressor; 
 coupling a second suction pipe leg to a suction port of the second compressor; 
 coupling the first and second suction pipe legs to a common suction pipe shared by the first and second compressors; 
 coupling a third sensor to the common suction pipe, the third sensor configured to transmit a third signal to a location remote to the third sensor, the third signal indicating one or more pressures of the refrigerant within the common suction pipe; 
 coupling the controller to the third sensor for receiving the third signal; 
 receiving, using the controller, the third signal indicating one or more pressures of the refrigerant within the common suction pipe; and 
 determining, using the controller, a superheat temperature of the refrigerant within the first compressor in response to the first pairing signal being generated using at least the first signal indicating one or more temperatures of refrigerant within the first discharge pipe leg and at least the third signal indicating one or more pressures of refrigerant within the common suction pipe. 
 
     
     
       20. The method of  claim 15 , further comprising:
 receiving, controller, a triggering input signal and in response to the triggering input signal causing a temperature increase of the refrigerant within the first discharge pipe leg of the first compressor. 
 
     
     
       21. The method of  claim 20 , wherein the triggering input signal indicates a partial load demand on the HVAC system. 
     
     
       22. The method of  claim 20 , wherein the triggering input signal indicates an initial powering of the HVAC system. 
     
     
       23. The method of  claim 20 , wherein the triggering input signal indicates a command for diagnostic testing of the HVAC system. 
     
     
       24. The method of  claim 15 , further comprising:
 the controller generating an alert signal indicating that the first sensor is not coupled to the first compressor in response to the second pairing signal being generated.